LONDON, Oct 11 (Reuters) - Brent crude oil reached itshighest in a month on Thursday, lifted by escalating tensionbetween Syria and Turkey, maintenance in the North Sea and asupply crunch in oil products.

November Brent crude rose $1.00 to $115.33 a barrelby 1346 GMT, after matching Wednesday's high of $115.59. U.S.crude climbed 93 cents to $92.18.

Turkey scrambled fighters and briefly detained a Syrianpassenger plane on Wednesday, suspecting it of carrying militaryequipment from Moscow, while Turkey's military chief warned of amore forceful response if shelling continued to spill over theborder.

"The Syrian situation is heating up and there are fearsabout Turkey, a NATO member, retaliating and contagion in theregion," said Bjarne Schieldrop, analyst at SEB in Oslo.

Worries about supply disruption caused by fears of violencein the Middle East and maintenance at the North Sea Forties oilfield have pushed Brent's premium to U.S. crude to its highestin a year at around $23.50 .

North Sea crude oil output from 12 production streams is setto fall by about 1 percent in November, according to Reuters'calculations, another potential source of support for Brent oilprices.

Firmer refining margins and steep backwardation in thegasoil market, where prices are higher for prompt delivery thanfor later dates, pointed to firm demand going into the northernhemisphere winter.

"At current prices, the upcoming winter will be the mostexpensive winter ever for the consumers using heating oil," saidOlivier Jakob at Petromatrix in Switzerland, adding thatgasoline prices were also high.

"All in all, after the high cost of driving and heatingthere will be at least one iPad less under the Christmas tree,"he said.

Global oil demand is looking weaker than previously forecastas the slowing economy continues to weigh on consumption, theU.S. government and the Organization of the Petroleum ExportingCountries (OPEC) said in reports.

On Wednesday, the U.S. Energy Information Administration(EIA) and OPEC cut their forecasts for growth in world oildemand in 2013, a day after the International Monetary Fund(IMF) lowered its economic growth forecasts for the second timesince April.

The EIA and OPEC reports are two of three major oil outlooksdue out this week, with the International Energy Agency torelease its October oil markets outlook on Friday.

Providing some positive news on the economy, the number ofAmericans filing new claims for unemployment benefits fell lastweek to the lowest level in more than four and a half years,U.S. government data showed on Thursday.

However, the backdrop was still downbeat. China's annualeconomic growth probably slowed for a seventh straight quarterin the July-September period to the weakest level since thedepths of the global financial crisis, a Reuters poll showed.

In the United States, crude stocks rose 1.6 million barrelslast week, industry group American Petroleum Institute said onWednesday, more than an 800,000-barrel build forecast byanalysts in a Reuters poll.

The EIA will release its weekly inventory report later onThursday. A poll of 12 analysts' forecast weekly U.S. stockpilesdata would show crude inventories up 800,000 barrels for theweek ended Oct. 5.